Manufacture of gasoline



Dec. 26, 1922.

R. F. BACON ET AL.

MANUFACTURE OF GASOLINE.

HLED OCT. 19. 1914.

alto plug 7 Patented Dec. 26, 1922.

UNITED STATES 1,439,683 PATENT OFFICE."

RAYMOND F. BACON AND BENJAMIN '1. BROOKS, OF PITTSBURGH, PENNSYLVANIA,ASSIGNORS TO GULF REFINING COMPANY, OF IITTSBURGH, PENNSYLVANIA, A

CORPORATION OF TEXAS.

MANUFACTURE OF GASOLINE.

Application filed 0ctober19, 1914. Serial No. 867,428.-

To all whom it may covwern:

Be it known that we, RAYMOND F. BACON and BENJAMIN T. BROOKS, residingat Pittsburgh, State of Pennsylvania, have invented certain new anduseful Improvements in the Manufacture of Gasoline; and we do herebydeclare the followin to be a full, clear, and exact description 0 theinvention, such as will enable others skilled in the art to which itappertains to make and use the same.

In Letters Patent of the United States glranted to us jointly withClinton W. Clark,

0. 1,131,309, is described the treatment of mineral oils for theproduction of a mixture of hydrocarbons, principally of the C H series,boiling below 200 C. This product may be conveniently designated asgasoline or light petroleum distillates, suitable for use in internalcombustion engines and is intended principally for such use.

The present invention is based upon the discovery that when workingunder like conditions of temperature and pressure to those specified inthe patent referred to, greater yields of gasoline are obtained by'using, as the charge for the still, the hereinafter described heavierpart of the distillate from crude petroleum, instead of either the wholedistillate boiling above approximately 150 0., or instead of a reducedcrude containing considerable proportions of asphaltic matter; and,furthermore, that, in such case, there is a considerable decrease in theamount of coke produced in the gasoline-making operation.

In the ordinary fractional distillation of crude petroleum (forinstance, Oklahoma crude or mixed base), the fraction distilled ofi'between the kerosene and the lightest lubricating oil cuts is known assolar oil and has a specific gravity (e. g., of about 0.86) andviscosity less than said lightest lubricating oils. .We have found thatthis solar oil fraction is of relatively low capacity as a crudematerial for the production of gasoline. For instance, in treating solaroil obtained from Oklahoma crude, the yield of gasoline, at a pressureof 100 pounds to the square inch and a temperature of 400 C., is from 8to 10% of the charge; whereas, when Oklahoma crude oil from which thegasoline originally contained in the oil is removed is treated under thesame conditions of pressure and, temperaturethere is' a yield of 18 to20% of .the charge. Still further, when the lighter fractions and thesolar oilhave first been fractionally distilled off from the crude oiland the heavy distillate substantially free from the heavy baseconstituents of the petroleum whose employment is characteristic of thepresent invention is collected separately and treated under the samecondi tions of pressureand temperature the yield of gasoline was foundto rise to from 28 to 30% of the heav distillate charge. This unexpectedand ra ical increase in yield of gasoline under like conditions oftreatment could not have been predicted from any information possessedby those skilled in the art, and constitutes an improvement ofcorresponding value and importance.

Referring further to the heav distillate which constitutes the materiatreated for the production of gasoline in accordance With the presentinvention, it may be said that it has the specific gravity and typicalafline, but, being a distillate, it is substan tially free from heavyresiduum or base constituents. The presence of arafline, the exactspecific gravity, the co or, and the like, will vary somewhat inindividual instances, within limits recognized in the art. However, a tyical crude oil will yield by ordinary distillation processes, say 40% ofgasoline and kerosene, about 30% of solar oil, and finally about 25% ofthe heavy oil referred to herein as heavy distillate.

In carryin out the invention, we prefer, as hereinbe ore indicated, toemploy the same range of temperatures and the same pressures thatcharacterize the treatment set fprth inlhe patent referred to, and,indeed, the same apparatus may be employed Oklahoma to advantage, all ashereinafter more fully set forth. We have obtained satisfactory yieldswith pressures as low as 60 pounds to the square inch, and, while theyield in creases at higher pressures, we do not ordinarily find it ofadvantage to increase the pressureabsolutely to the upper limit of 300pounds; in fact, there is usually no such material advantage in yield inraising the pressure above say 250 pounds as would compensate for theincreased expense of so doing. Indeed, for safety of operation, it willsufiice ordinarily to conduct the operation at a pressure of say topounds per square inch and at a temperature rangin from 350 C. to 500 C.

Vhile we recommend the general form of apparatus shown in theaccompanying drawing as appropriate to the practice of the invention, itwill, of course, be understood that we do not limit ourselves thereto,inasmuch as the characteristic feature of the invention consists in thediscovery hereinbefore carefully pointed out, to wit, that by employingthe heavy distillate referred to a greater proportion of the complexhydrocarbons are cracked up into the simpler gasoline hydrocarbons,under the same conditions'of pressure and temperature, and that thisincreased yield in the desired product is likewise accompanied by adiminished deposit of coke. in the pressure still.

It will, of course, be understood that the optimum results obtainableare produced when solar oil is substantially absent from the heavydistillate, inasmuch as solar oil yields proportionately less gasoline.In practice, however, a certain minor amount of solar oil maynevertheless be tolerated in the heavy distillate without seriouslyinterfering with the percentage ield and, indeed, in some of the so-callparafline distillates a notable quantity of solar oil is present, say,in some instances, up to 10 to 15%. The treatment of such a distillatewe regard as within the broad scope of our invention. While we do notrecommend that, in any case, the amount of solar oil shall exceed thatpercentage, we prefer that its percentage be as low as is economicallyfeasible.

In the accompanying drawing, Figure 1 represents, partly in section, andpartly in elevation, a form of apparatus suitable for the practice ofthe invention; Fig. 2 represents a partial view of another modificationof the invention, showing its applicability to advantage in multipleunits.

Similar letters of reference indicate simi lar parts in both the views.

Referring particularly to Fig. 1, A indicates a storage tank for thepetroleum hydrocarbons to be treated, and B indicates a pump fordelivering a regulated. supply therefrom to the still through theconduit (1.

In Fig. 1, is shown a single unit consisting the pump of a tube 1), ofsteel or other suitable metal and whose length is preferably QO-sft. ormore, when the internal diameter of the tube is 6 inches. The heatingzone of the tube is intermediate of its ends and, in the form shown inFig. 1, consists of a fire brick chamber C having suitable air inlets,as d, and a suitable exit opening, as e, for the products of combustion.The chamber C may receive its heat from any convenient source, as, forinstance, a series of annular gas burners, K, supplied with a mixture ofair and gas rom the gas conduitl) whose branches g terminate ininjecting tips, as shown, and which draw in with them a suitable supplyofair through the bell h opening into the atmosphere. At its lower end,

the tube Z) communicates With a tar and coke receiving receptacle E,located below, outside of the heating zone.

At the beginning of the operation, the

charge of oil to be cracked and distilled is established up to the levelindicated in Fig. 1, that is to say, at a level slightly higher than theinternal wall of the top of the heating chamber C. This level of thebody of oil is kept Eractically constant, by means of which supplies oilto the interior of the tube as the cracking and distillation proceed.Accordingly, the. products of combustion do not come into direct contactwith an portions of the tube not occupied by the liquid oil, andconsequently, the danger of destructive distillation of any portion ofthe vapors by coming into contact with overheated ortions of the tubeabove the zone of liqui oil is minimized and the formation of anadhering layer of coke upon such portion of the walls of the tube isavoided.

The free portion of the tube extends above the furnace setting, asshown, for a distance of say 5 feet. The vapors pass, by means of thepipe 2', to the condenser coil J, contained within the coolingreceptacle F. The condenser coil is provided at its end with a valve isand discharges into the receptacle G. The uncondensed gases and vaporsfrom the receptacle G pass by the pipe Z into a bod of oil containedwithin the receptacle wherein such particles of oil as are contained inthe residual gases are trapped and recovered. The surplus gases andvapors pass off through the conduit m. At the bottom of the receptacle Ea pipe n conveys the residual tar and coke to a receiving tank I. theflow being under the control of a regulable valve 8.

From the foregoing description of the purposes of the invention, and ofthe construction of the apparatus shown in Fig. 1, the mode of operationwill be fully a parent. The receptacle E and the tube E, are filled tothe level indicated, and the annular burners f are ignited. The temperature rises to the range hereinbefore referred to, that is to say, 350 C.to 500 0., and the pressure is likewise permitted to rise, by shuttinoff the valve K either wholly or partial y, as the case may be, untilthe pressure gage t indicates the pressure desired, that is to say, aressure within the range of 60 lbs. to 300 l 5. per square inch.

During the cracking and distilling operation, any particles of tar andcoke that may be formed in the body of the distilling oil tend to fallthrough the vertical heating zone, by gravity, into the receiving spaceof the chamber E. A relatively small amount of tar and coke will, inthecourse of time, build up upon the vertical walls of the tube B withinthe heating zone, but these accumulations are relatively unimportant andslow of formation, and, should they become excessive, may be readilyremoved by the use of any ordinary boiler flue cleaner, or the like. Thepetroleum residue containing the coke accumulating in the receptacle Eis drawn off from time to time through the pipe it into the receiver 1.In the form of the invention-indicated in 'Fig. 2, there is shown aseries of individual tubes 5, having at the bottom a common header E"corresponding in function and location to the receptacle E of Fig. 1.The tubes 6 are located in a heating flue C supplied with a flow of hotproducts of combustion from any suitable source, so as to heat the tubesto the high temperatures hereinbefore referred to, the header E beinglocated in a cooler space below the'heating flue. a indicates a supplypipe communicating with the interior of'the several tubes 6, so as tofurnish oil thereto. So also, the pipe 1" constitutes the exit pipe forthe vapors. 'The supply pipe a and the exit pipe n from the header E areconnected by the cross-connecting pipe '0 having a valve w andcontaining the liquid level gage w so that the operator will be able toknow at any time the oil level within the several tubes 71. The mode ofoperation of this modification will be clear from what has been said inregard to the mode of operation of the form of the apparatus shown inFig. 1, and need not be further laborated.

lVhat we claim is:

1. The method of producing from petroleum oils containing as haltic baseconstituents a product inten ed particularly for use as fuel forinternal combustion engines, which consists in subjecting a heavydistillate of such pertoleum having a specific gravity above 0.860 andwhich is substantially free from lower boiling solar oil having aspecific gravity of about 0.860 and below, and which is alsosubstantially free from heavy base constituents of the petroleum, to acombined crackin and distilling operation at a pressure within the rangeof 60 pounds to 300 pounds per square inch, and at a temperature withinthe range of 300 C. to 500 C.

2. The method of producing from petroleum oils containing asphaltic baseconstituents a product intended particularly for use as fuel forinternal combustion en ines, which consists in subjecting a heavyistillate of such petroleum containing a considerable proportion ofnaphthene hydrocarbons, said distillate being substantially free fromthe lower boiling 011 having a specific avity of about 0.860 and below,and sai disti late being also substantially free from heavy baseconstituents of the petroleum, to a combined cracking and distillingoperation at a, pressure within the range of 60 pounds to 300 pounds persquare inch, and at a temperature within the .range of 300 C. to 500 C.

3. The method of producing from petroleum oils a product intendedparticularly for use as fuelfor internal combustion engines, whichconsists in subjecting a heavy distillate of mixed base etroleum, whichheavy distillate has a speci c gravity of above 0.860 and issubstantially free from the lower boiling solar oil having a specificgravity of 0.860 and below, and is also substantially free from heavybase constituents of the petroluem to a combined cracking and distillingoperation, at a pressure within the range of 60 pounds to 300 pounds persquare inch and at a temperature within the range of 300 C. to 500 C.

4. The method of producing from petroleum oils containipg asphaltio baseconstituents a product intended particularly for use as fue for internalcombustion engines, which consists in subjecting a heavy distillate ofsuch petroleum having a specific gravity above 0.860 and which issubstantially free from the lower boiling solar oil having a specificgravity of about 0.860, and below, and which is also substantially freefrom heavy base cdnstituents of the petroleum, to a combined crackin anddistilling Operation, at a pressure within the range of 60 pounds to 300pounds per square inch, and at a temperature within the range of 300 C.to 500 C. progressively removing from the cracking and distilling zonethe no I particles of tar and coke reduced therein petroleum, to acombined cracking and distilling operation at a pressure within therange of 60 pounds to 300 pounds per square inch, and at a tem Jeraturewithin the range of 300 C. to 500 7. progressively removing from thecracking and distilling zone the particles of tar and coke producedtherein,

and depositing them out of contact with the walls of the cracking anddistilling zone.

6. The method of producing from petroleum oils containing asphaltic baseconstituents a product intended particularly for use as fuel forinternal combustion engines, which comprises separating from crudepetroleum, containingsuch asplialtic base constituents a heavydistillate of specific gravity 1 ,439,ees

above 0.800 and substantially free from base constituents and'from lowerboiling distillate having a specific gravity of 0.860 and below andsubjecting said heavy distillate to a'combined cracking and distillingoperation at a pressure within the range of 60 pounds to 300 pounds persquare" inch, and at a temperature within the range of 300"'(. to

In testimony ,whereof we affix our signatures, in presence oft\\'o\vitnesses.

RAYMOND, F, BACON. BENJAMIN 'I. BROOKS.

\Vitnesses:

H. H. SMITH, S. C/PERRING.

Dl scl AlMEFb -1,439,683.- aymond F. Bacon and Ben'mnin 7'. Brooks,Pittsbur h, Pa. MANU- ncrmu: or Gnsonnn. .Patent da December 26, 1922.Discfilimer filed August 25, 1930, by theassignee, Gulf RefiningCompany.

--Tberefore disclaims frdm thesoo or meaning of claims 1, 2, 3, 4, 5,and 6 of skid Patent 1 439583 anymethdd of p u'cin a product intendedparticularly for use as fuel for mternal-eombustion engines whighincludes subjecting petroleum oils to a pressure within a' range below100 pounds per square inch.

[Ofim'al Gazette September 16, 1980.]

